49 Fun Facts About Roofing

Henry Reynolds of which city invented asphalt shingles, North America's most common roofing?

Henry Reynolds of Grand Rapids, Michigan cut the first asphalt shingles from asphalt roll roofing; they were in general use in parts of the US by 1911, and by 1939 America made 11 million squares a year.

In what year were asphalt shingles first used on a roof?

Asphalt shingles were first used in 1903; a National Board of Fire Underwriters campaign against wood shingles helped push them into the mainstream over the following decades.

In 1897, what was first added to the surface of asphalt roofing to make it more durable?

Slate granules, crushed and pressed into the asphalt, were the first mineral surfacing; later experiments included mica, oyster shells, dolomite and fly ash, while the underside gets talc or sand so bundled shingles don't stick.

By 1882, what share of Britain's slate came from Wales?

Wales produced 92% of Britain's slate by 1882; the two largest quarries alone supplied half of it, and the quarrymen worked in partnerships called 'bargains'.

Large-scale Welsh slate mining began in 1782 with the opening of which quarry near Bethesda?

Penrhyn began as the Cae Braich y Cafn quarry in the Ogwen Valley, developed from 1782 under Richard Pennant, and grew into one of the largest slate quarries in the world.

Slate splits into smooth flat sheets for roofing because of a property called what?

Fissility, the tendency to split along fine parallel planes, lets slate be riven into thin sheets; the same property suits it to floor tiles and billiard-table beds.

A 2013 report estimated how many properties in the UK still had a thatched roof?

Most are long straw, combed wheat reed or water reed, and more than 80 percent of the water reed used is now imported.

How much well-managed reed bed does it take to produce enough water reed to thatch an average house?

Around 4–5 acres of well-managed reed bed yields enough water reed for one average house; large reed beds have been rare in England for centuries, so most reed is imported from Turkey, Eastern Europe, China and South Africa.

Which French ruler's rebuilding of Paris made the mansard roof fashionable in the 19th century?

Napoleon III's Second Empire rebuilding of Paris under Haussmann put mansard roofs on boulevards across the city, and the look was copied worldwide as Second Empire architecture.

A gambrel roof, the classic American barn shape, has how many slopes on each side?

Two slopes per side define a gambrel, the upper one shallow and the lower one steep; Europeans often call the same shape a mansard, a term Americans reserve for the four-sided version.

Which shape is recommended in hurricane regions because it has no flat gable ends to catch the wind?

Hip roofs slope on all four sides, so there is no flat gable end for wind to push on; in hurricane country they should also be steep, since wind over a shallow hip creates lift like an aeroplane wing.

What is the usual term for a slender dormer-like window set into a Gothic church spire?

Lucarne, French for a dormer window, is the usual term for the slender gabled openings set into a Gothic church spire.

In US roofing, slope is expressed as inches of rise over what horizontal run?

12 inches is the standard run: a roof rising 6 inches over that foot is called a 6:12, a convention that leaves pitch, rise over span, as a separate measure.

What pitch does a flat roof have?

Zero pitch defines a flat roof in name, though in practice even a flat roof is laid with a slight fall, typically a quarter inch per foot, so rainwater runs off.

The strip of flashing along the downslope face of a chimney is traditionally called what?

An apron is the flashing piece across the chimney's downslope face; step and counter flashing dress the sides, and a back gutter takes the uphill run-off.

According to the Oxford English Dictionary, the word 'eaves' comes from an Old English word meaning what?

Edge is the meaning of the Old English efes, a singular noun; that history is why 'eaves' serves as both singular and plural in modern English.

Which people first brought rainwater gutter systems to Britain?

The Romans introduced gutters, and the technology was lost after they left until the Normans reintroduced it; the White Tower at the Tower of London was fitted with gutters.

Who patented 'indented or corrugated metallic sheets' in 1829, giving the world corrugated iron roofing?

Henry Palmer, architect and engineer to the London Dock Company, took out the 1829 patent; once it expired, corrugated galvanised iron spread worldwide as a cheap, light roofing.

Overlapping tiles called imbrex and tegula covered the roofs of which ancient civilisations?

Greece and Rome roofed with the flat tegula laid first and the curved imbrex capping the joints; the pattern survives in Mediterranean terracotta roofs.

In which country is Lerna's 'House of the Tiles', where thousands of Bronze Age terracotta roof tiles were found?

Greece is the site: the House of the Tiles at Lerna in the Argolid, an Early Bronze Age building of around 2500 BC, collapsed under a roof of fired terracotta tiles.

The first sports venue with a retractable roof was in which US city?

Pittsburgh's Civic Arena, opened in 1961 for the Civic Light Opera and later home to the Penguins, had a retractable domed roof; it was demolished in 2012.

How many tiles cover the shells of the Sydney Opera House?

About 1,056,000 tiles (1,056,006 by the usual count) cover the shells, in glossy white and matte cream laid in a chevron pattern on the precast lids.

The Sydney Opera House's roof tiles were manufactured in which country?

Sweden supplied them: the firm Höganäs made the tiles, though the architect Jørn Utzon was Danish; the building opened in 1973, 16 years after his competition win.

Almost 2,000 years after it was built, the Pantheon in Rome still holds what record?

The Pantheon, completed around AD 126, has the "Largest unreinforced concrete dome" ever built; the interior diameter and the height to the oculus are both about 43 metres, so a perfect sphere would fit inside.

The Notre-Dame de Paris roof that burned in April 2019 was largely oak from which century?

The 1200s supplied most of the "forest" of oak beams, felled early in that century; the timbers were sheathed in lead, and the stone vaults below largely contained the collapsing roof.

Who coined the term 'geodesic' for the dome design he popularised and patented in 1954?

Buckminster Fuller coined 'geodesic' and patented the dome in 1954, though Walther Bauersfeld's planetarium dome, 'The Wonder of Jena', had opened in Germany in 1926.

Over decades, a copper roof weathers to which distinctive colour?

Green is the colour of verdigris, the patina copper develops after years of weathering; the look is so prized that pre-patinated copper sheet is sold to get it from day one.

According to historian Wolfgang Born, the onion dome originated where?

Umayyad-era mosaics show early bulbous domes; the shape is now most associated with Russian Orthodox churches.

The oldest surviving rooster-shaped weather vane, the Gallo di Ramperto, was made in which year?

The Gallo di Ramperto dates from 820 and sits in the Museo di Santa Giulia in Brescia; Pope Gregory I had called the cockerel 'the most suitable emblem of Christianity'.

The Tower of the Winds in ancient Athens carried a weather vane in the shape of which sea god?

Triton, the merman, topped the tower in bronze, holding a rod that swung to point into the wind; the Tower of the Winds is one of the earliest known weather vanes.

Where does the name of the 'widow's walk', a railed rooftop platform on old coastal houses, supposedly come from?

The romantic story is "Wives watching for husbands' ships" from the railed platform; in some towns they were "captain's walks", and architecturally the feature is a variation of the Italianate cupola.

The New England saltbox house is named after its resemblance to what?

Named for "A slant-topped wooden salt box", the lidded kitchen box salt was kept in, the house is two storeys at the front and one at the back, giving the rear slope its long run.

Which architect first designed a V-shaped butterfly roof, for a 1930 holiday house in Chile?

Le Corbusier drew the butterfly roof for the Maison Errázuriz, an unbuilt Chilean holiday house; it became a mid-century icon when William Krisel put it on tract houses in Palm Springs from 1957.

Why did the Houston Astrodome paint sections of its roof panes white in 1965?

"Glare stopped players tracking fly balls" through the Lucite skylights, so panes were painted over; the fix killed the natural grass, the Astros played on painted dirt, and in 1966 the dome got the first AstroTurf.

Domestic chimneys first appeared in large northern European dwellings in which century?

The 1100s saw the first domestic chimneys in big northern European houses; England's earliest surviving example, at Conisbrough Castle in Yorkshire, dates from about 1185.

A traditional Scandinavian sod roof sits on layers of which material laid over the roof boards?

Birch bark, laid in several overlapping layers over the boards, is the waterproof membrane; the sod above holds it down, and until the late 19th century this was the standard roof on rural Norwegian log houses.

Which US city hall's green roof, planted as a microclimate experiment, is one of the country's best-known?

Chicago City Hall's rooftop garden, completed in 2001, was planted to test how a vegetated roof cools the urban heat island; the city then wrote rooftop-planting incentives into its building rules.

An ice dam forms where on a heated building's sloped roof?

At the eaves the roof overhangs unheated space, so meltwater running off the warm attic refreezes there, backing water up under the shingles.

Modern timber roofs are mostly framed with pairs of common rafters or with what prefabricated components?

Wooden trusses, factory-built and joined with pressed metal connector plates, frame most modern timber roofs; historic buildings relied instead on principal rafters and purlins or heavy timber roof trusses.

Per the US Bureau of Labor Statistics, roughly how many people worked as roofers as of May 2022?

Roofing is ranked among the most dangerous construction trades because of falls and extreme heat.

In Australia, what is the tradesperson who builds a house's timber roofing frame called?

A roof carpenter builds the timber frame in Australian usage, while "roofer" there means the trade that fits the cladding of tiles or metal sheeting.

Wimbledon's Centre Court gained a retractable roof in which year?

The roof was first used in 2009, letting play continue in rain and into the evening up to the 11 pm curfew imposed by Merton council.

What are wooden roofing pieces called when they are split from a log rather than sawn?

Shakes are split from a log along the grain, giving a rough, thick face, whereas shingles are sawn smooth on both sides and laid thinner.

Whose paintings suggested Fiddler on the Roof's title and inspired its original set design?

Marc Chagall's paintings of fiddlers floating over village roofs gave the musical its title, and Boris Aronson's original sets echoed his style; the writers had considered simply calling it Tevye.

The word 'roof' comes from Old English hrof, which also figuratively meant what?

Heaven or sky was the figurative sense of hrof, alongside "top, summit"; English alone kept the word, while other Germanic languages use forms related to thatch, such as German Dach.

In the UK, what is the condition called when a slate roof's corroded fixing nails let slates slip?

Nail sickness is the term for corroded iron fixing nails letting sound slates slip, a common failure on Victorian roofs; copper nails avoid it, and a slate roof can then last well over a century.

The stone arch or vault dominated major roof structures for about 2,000 years until which 1851 building?

Paxton's Crystal Palace, the iron-and-glass hall of the 1851 Great Exhibition, showed what iron framing could do; Roman stone arches had spanned up to about 45 metres, and iron beams then took over.

Which French cathedral got its vast copper roof after an 1836 fire destroyed the timber one?

Chartres lost its medieval timber roof to fire in 1836 and was re-roofed in copper on an iron frame, which weathered to pale verdigris; lead was the more usual church roofing.

Which two North American cities are cited as requiring a minimum roof slope of 6 in 12 because of snow?

A pitch of 30 degrees helps steep roofs shed snow, as in Germany and Holland; Alpine chalets buck the trend with gentler stone roofs.